Melt butter in skillet and saute the chopped vegetables until translucent.,Mix vegetables with crumbs, soy sauce, thyme and pepper.,Moisten with stock or melted butter if it seems too dry. Rinse and dry fish.,Place in a well-greased baking dish or foil lined pan.,Brush inside and out with melted butter.,Sprinkle with a little salt and stuff loosely.,______,It is done when fish flakes easily with a fork at the thickest part.